Grants List

University of East Anglia

Deciphering the role of marine microbial communities in recycling the smallest carbon nutrients

In support of developing and applying cutting-edge molecular ecology methods to create a deeper understanding of how microorganisms that rely on small carbon molecules for food are active in deep and shallow marine habitats.

Title:
Deciphering the role of marine microbial communities in recycling the smallest carbon nutrients

Small carbon compounds such as methane, methanol and methylamine are surprisingly abundant in the oceans. These compounds may serve as food sources for some marine bacteria that are specialized microbes called methylotrophs. In this project we are investigating where these types of bacteria occur in the marine environment, how they can use these compounds as sources of carbon and energy and find out what contribution they make to the microbial food webs in the oceans. The research involves developing new molecular biological methods by which we can study bacteria in the environment without having to cultivate them in the laboratory. The hope is that these methods can then be applied to many other groups of microbes in the seas to determine “who is doing what” in the environment.

The overall objective of this project is to investigate the role of aerobic methylotrophic bacteria in key biogeochemical cycles in the marine environment and to use these bacteria as a model system to develop a suite of techniques that will answer key questions about carbon and nitrogen cycling in marine microbial food webs. This will include the use of functional metagenomics, based on the technique of DNA Stable Isotope Probing, single cell ecophysiological methods (Raman-FISH) to define populations of active methylotrophs in the marine environment that are carrying out specific processes i.e. “who eats what, where and when”. The research will facilitate the development and use of a powerful suite of generic molecular microbial techniques to define microbial interactions and investigate the flow of nutrients in marine microbial ecosystems. Thus we will use methylotrophic bacteria as model systems to develop focussed “functional metagenomic” techniques as a generic technology for marine microbial ecology, to identify the active methylotrophic bacteria responsible for cycling of methane, methanol and methylamines in the marine environment and their contribution to the marine food web, to determine the environmental parameters which regulate the cycling of methylotrophic compounds in the marine environment and to investigate how methylotrophs respond to environmental change in marine systems at the whole system (metagenomic) community level and at the single cell level. We will test the hypothesis that methylotrophic bacteria constitute a significant proportion of the marine microbial community and play a key role in cycling of carbon/nitrogen in the oceans and the marine food web.